I'm sure its right under my nose and i fail at the internets but I can't find a recent, definitive guide for dk tank gems. The enchant post on the blizzard's dk forums looks correct but its not very recent. I play a main paladin whose offspec is prot and was able to find an extremely detailed and updated guide on gems/enchants on maintankadin but can't find anything similar for dk. Ret, protpaladin, and all three trees of dk dps have very detailed posts on elitist jerks but there is only a much briefer one for tanking that focuses solely on the spec and 'best in slot' lists.
Is there a list somewhere? The dk tank in my guild uses a different gem setup than is suggested for prot paladin (dodge/stamina gems in red slots with appropriate bonuses instead of agi/stam) and i saw this also suggested in a blizzard forum post.
Enchant for armor or stamina wherever possible (armor on cloak and gloves, stamina everywhere else). 275 hp to chest. +30 stam in all sockets except one red socket where you put a purple gem to hit your 2% armor meta gem bonus. Select the single socket with the most stam in the bonus for this (it will be either helm with 12 stam or belt with 9). This not only goes for DKs but all tanks.
Yeah, the differences with 10 dodge and 10 agi are really such small things to debate anyway, that's why I never make a suggestion on which purple to use. I've used both, I've used expertise and I never noticed a difference between the 3.
So its not even worth going with a green def/stam gem with a slot bonus of +9 sta? I guess i should have indicated that i'm not going to have a lot of i264 or even i251 gear for quite a while. I can easily make the defense cap (at 536 with no gems and only head/weapon enchant) but my understanding for prot paladin is that until you're nearing full icc gear its still a good idea to at least use def/stam in yellows and usually agi/stam (or dodge/stam for dk apparently) in reds with a bonus of 9sta or more.
I'm one of the few that don't go the stack stam - ignore everything else route. While I'll stack it, I like to make sure I'm hit/expertise (soft) capped before I go throwing a blue in every socket; and by capped I mean getting to the relevant cap through gems/gear or getting to the point where a food buff will make up the difference. All the stam in the world is useless if the mob ain't hitting on you. Doing this I still go around 43k unbuffed on my DK.